Treatment oe mineral oils



Nov. 6, 1928. I 1,690,772

T. G. DELBRIDGE ETAL TREATMENT OF MINERAL OILS Filed May 21, 1925 2 Sheets-Sheet 1 STOCK Acm TREAT sE rTLE SOUR OIL SL-UDGE HE T AIRPLOW soun :SILLHOTI wATER's 50% OFF ADD SLURRY OF OIL e, TW CE USED CLAY AIR BOLOW SETTLE PARTIALLY TREATED OILLHOT] SPENT cLAY SLURRY ADD sLuRRv 0F Oil. 5 ONCE USED CLAY AIR BLOW To RECOVERY SETTLE PARTIALLY TREATED OILIHOT) ADD FRESH AND/OR SLURRY OFOILA'r REVIVIFIED CLAY TWICE USED CLAY AR ow REUSE A5 ABOVE SETTLE 1, v5 TREATED OIL(HOT) sLuRRY OF OIL AND ONCE USED CLAY ER REusEIxs ABOVE I MI-(HOT) PARTIALLY sPEN r CLAY CONTAINING OIL TO STORAGE R T0 RECOVERY FIEUSE AIR WATER AC D OIL Z Y/AML ATTORNEY.

Nov. 6, 1928. 1,690,772

' Y r. G. DELBRIDGE ET AL TREATMENT OF MINERAL OILS Filed May 21,- 1925 2 Sheets-Sheet 2 1 5 STgCK /b ACIDTREAT SETTLE v SOUR on. SLUDGE HE AT Am BLOW WATER AND soun OIL(HOT) 502 OFF ADD CLAY AFR BLDW OR FHETER SETTLE & FINISHED OIL, CLAY F'LTER CAKE CLAYR: OIL OILCONTAINJNG DECOLQ RlZED -0R; suianv CLAY T E OVERV i T0 STORAGE 0 R REUSE REUSE OR FILTER SEPARATE FlNlSHED OIL CLAY FILTER CAKE To STORAGE OR TO RECOVERY REUSE AIR JZ F/L 75/? T0 6701 6465 /I/ VE/VTURS:

72 gaw "A .m y mj LxzAzi/fi i-"iterated Nov. 6, 1928.

UNlTED STATES PATENT OFFlCE.

THOMAS G. DELBRIIDGE AND HENRY F. DUKE, OE PHILADELPHIA, PENIDTSYLVANIA, AS- SIGNORS T0 THE ATLANTIC BEFINING COMPANY, OF PHILADELPHIA, PENNSYL- VANIA, A CORPORATION OF PENNSYLVANIA. I

TREATMENT OF MINERAL QILS.

Application filed May 21, 1925.

Our invention relates to the purification and dccolorizatiou of mineral oils, and particularly crude petroleum, its distillates and residues, by contact with finely divided decolorizing or absorbing materials, such as fullers earth, acid-treated California clay, carbonaceous materials, and equivalents.

In accordance with our invention, mineral oils of the character above referred to, and especially lubricating stocks or oils destined for lubricating purposes, previously acid.- treated or not, and while at temperature suitable to reduce their viscosities it neces sary, are blown or agitated by air or equivalent, either before, during or after addition of finely divided clay or equivalent decoloriziug or absorbing material.

Further in acordance with our invention, if the oil or stock has been acid-treated, the resultant sour oil is blown oragitated with air or equivalent while at suitably elevated ten'iperature, to remove moisture and compounds such as sulphur dioxide, or the like, in solution or entrained in the oil, and thereafter the dry sour oil, while at elevated temperature, is blown or agitated with air or equivalent in the presence of the finely divided clay or equivalent material.

Further in accordance with our invention, the finely divided clay may be added in the form of a slurry of oil and clay; and more particularly, the clay first added to the oil to be treated may be in the form of a slurry of oil and. clay, which latter has been one or more times used in a process of the general character above referred to.

Further in accordance with our invention, particularly in a continuous process, involving" the addition of clay and blowing with air or equivalent in. successive stages, fresh and /or revivified clay is brought into mixture with the oil and blown with air or equiv alent in a later stage ot the process, and in an earlier stage the clay after use in the actoresaicl later stage is added in any suitable term. as for example a slurry of oil and clay.

it is a characteristic of our invention that th-zoil during treatment it maintained at elevated. temperature is not or need not be rapidly or artificially cooled; that the temperature is not such that the oil will be to a material. degree affected as to color; that r not materially affected by the air gas utilised in Pr.

Serial No. 31,744.

ing the oil; that the temperature is or need be only such as to effect suitably low viscosity for convenient manipulation; and that the color of the finished oil is stable or does not darken upon standing.

Our invention resides in the method of the character hereinafter described and claimed.

For an understanding, of our method, reference is to be had to the accompanying drawings, in which:

Figure 1 is a chart or flow sheet illustratone of various continuous multi-stage processes comprehended in our invention.

Fig. 2 is an illustration of one of the systems or forms of apparatus which may be utilized for carrying out a method of the character indicated in Fig. 1.

Fig. 3 is chart or flow sheet illustrating one or various batch processes comprehended in our invention.

Fi 4- is an illustration of one of various systems or forms of apparatus utilizable in carrying out a method of the character indicated in Fig. 3.

The oil purified and decolorized may be of any character capable of improvement in substantial degree by our process. There may be treated those oils which are normally acid-treated and thereafter neutralized by alkali; there may also be treated those oils which, in ordinary refinery practice, are not acid-treated. but merely percolated through tullers earth or equivalent, generally in granular state. In accordance with our process, the last mentioned type of oils may or may not be given a preliminary acid treatment depending upon conditions. Thus. for example, in the case of those oils which would require relatively large quantities of clay or equivalent for decolorizing them. we may first effect acid treatment materially to reduce the amount of clay required. In any event. with any character of oil aforesaid, it is characteristic of our process that at some stage the mixture of oil, with clay or equivalent is blown or agitated with. air or equivalent,or agitated by any means while in contact with air.

Referring to Figs. 1 and 2, an oil, such for example as may he benefited. by or require acid treatment. is delivered through the pipe fl into the agitator tank or chamber a, and mid, at

all

strength, preferably 66 Be. or stronger, and f the Order of t0% of that usually required for acid-alkali treatment of the same oil, is introduced through the pipe 2, and the mixture agitated by air or equivalent introduced under pressure through the supply pipe 3 and thence through the perforated distributor pipes 4 into the mixture, which is so agitated, for a suitable period, for example, about 45 minutes, until the re action is complete, whereupon the agitation is discontinued and the'resultant sludge "is permitted to settle, is drawn oil through the valve-controlled pipe 5 and pumped to the acid recovery plant. To ensure simultaneous settlement from the oil while in the chamber A of the finely divided particles of sludge or pepper which would otherwise remain insuspension in the oil, a small quantity of water, as of the orr. er of 0.3%'

to 0.5% of the oil, is added near the end of the aforesaid agitation, as through the water supply pipe 6. It will he understood, however, that any other suitable or equiva lent method may be utilized for settling or removing the fine particles of sludge, which is desirable for econom in clay and air blowing subsequently used.

The sour oil is then drawn oil through the pipe 7 terminating adjacent the bottom of the chamber A in the pivoted or swinging pipe 7. The removal of the sour oil upwardly in the manner indicated, as distinguished from drawing it off through the pipe 5, ensures that a minimum of the aforesaid finely divided sludge or pepper will be carried ofi with the sour oil. This is of advantage, for the presence of the sludge particles in the sour oil causes darkening when the oil is heated, and increases the quantity of clay required for treatment. The sour oil so drawn off is delivered by pump P to suitable storage tank S of sufcientIy great capacity to holdsuccessive batches of sour oil delivered thereto, and so always to l'i'a-ve on hand a suliicient supply of sour oil to practice our purifying and decolorizing process continuously.

The oil after acid treatment and removal of sludge, including the tin'ely divided sludge or pepper, is a substantially com pletely de-sludged acid-treated or sour oil. By pump Phthe sour oil is preferably continuously delivered through the pipe 8 through the coil 9 ofthe heater P), of any uitable type,such, for example, in which the heat is derived from steam. In the heater B the oil is raised to a temperature "of the order of 150 F. to 210 F.,

temperatures the oil is much less susceptible to discoloration.

The hot sour oil passes from the heater l3 into the chamber or dehydrator C, where the oil is blown by air or equivalent delivered under pressure through the supply pipe 10 and through the perforated distributor pipes 11 into the oil. The air blowing, continued for a period of the order of onc half hour, removes water and other compounds, such,for example, sulphur dioxide, the removal of which and of moisture at this stage, prior to contact of the oil with the clay or equivalent, is of advantage in materially decreasing the quantity of clay required for decolorization and purification. This increase in. elficiency of the clay effected by this step may be due to several causes. First, the removal of the sulphur dioxide dissolved or entrained in the oil eliminates the necessity for neutralizing it with the clay, and thereby decreases the amount of clay otherwise necessary. Second, the removal of moisture from the oil is much more compl te than in the usual process, and, since excess moisture materially decreases the decolorizing power of the clay, the efiliciency of the clay is in effect enhanced. Third, this preliminary air blowing effects polymerization of or other change in-the color-imparting bodies in the oil to render them more readily removable by the clay. In any event, the fact is that the efficiency of the clayis materially increased or enhanced by this preliminary air blowing in the chamber C, and it shall be understood that the foregoing explanation of its cause shall not be limitive of our invention.

The blowing with air or equivalent has the further advantage in that relatively low temperatures of theorder aforesaid may be utilized and yet etYec-t sufiiciently high de gree of dehydration.

In lieu of. air for the preliminary treatment of the oil in advance of its contact with clay or equivalent, there may be uti lized any equivalent gas, whether or not containing oxygen, through an aeriferous or oxygen-containing gas is preferred; and in the appended claims there is utilized for brevity the term air to include air and its equivalents.

The hot, dry, sour oil, substantially free of sulphur dioxide and the like, overfiows through the pipe 12 into the agitator tank or chamber D, into which is introduced also through the pipe .or line 13, from a later stage of the process, a slurry of oil and clay. the latter previously used twice in later stages of "the process, but still retaining substantial purifying and decolorizing power. The mixture of oil and clay is agitated or blown with air or equivalent introduced under pressure through the supply pipe 14 and through the perforated distributor pipes 15 into the. mixture. The partially spent clay more or less neutralizes thesour oil and reacts therewith partially to purify the oil, and the clay itself becomes substantially inactive or exhausted. The mixture of spent clay and partially decolorized oil overflows through the pipe 16 into the settling tank E, where nearly all the clay settles to the bottom and is conducted through pipe 17 for treatment to separate therefrom the asso ciated oil by any suitable process.

The partially decolorized and purified oil, substantially free of clay, overflows through the pipe 18 into the agitator chamber or tank ll, into which is introduced also through the pipe or line 19 a slurry of oil and oncc used clay. The oil and clay mixture is agitated. or blown in the chamber F by air or equivalent introduced under pressure through the supply line 20, and through the perforated distributors 21. The decolorizing power of the once-used clay is further reduced, but the clay is not rendered entirely inactive; and the partially decolorized and purified oil is further purified, as by further partial decolorization and neutralization. The oil and clay mixture overflows through the pipe 22 into the settling tank G, to the bottom of which nearly all the clay settles, and a slurry of oil and clay is removed through the pipe 23 and forced by the pump P through the pipe 1.3, as aforesaid, into the agitator tank D, where the oil first comes into contact with clay.

The oil containing a slight amount of clay overflows from the settling tank G through the pipe 24: into the agitator tank or chamber H, where fresh and/or revivified finely divided clay is introduced, as through a chute The oil and clay mixture is agitated or blown by air or equivalent introduced under pressure through the supply pipe 26, and the perforated distributor pipes 27. The fresh and /or revivitied clay at this stage completes the purification, decolorization and neutralization of the oil, and is itself reduced somewhat in activity, as, for example, to an efficiency of about one-third, more or less, of fresh clay. The mixture of oil and clay overflows through the pipe 28 into the settlillq tank J, where nearly all of the clay settles to the bottom and is removed in a slurry of oil and clay through the pipe 29 and. forced. by the pump P through the aforesaid pipe 19 into the agitator tank l where the second stage of clay treatment is effected, as above described. The purified oil from which the major portion of the clay has settled overflowsthrough the pipe 30 and is forced by pump P through thefilter K, of any type suitable for removal of the small 'ty of clay suspended in the oil. The purified. or finished oil passes from the filter through the 3). to storage, it being understood, however, that the filtering op eration may be omitted. If a filter, such as K, be used, the filter cake separated thereby may be re-used in any of the stages of the process, or may be subjected to a recovery process.

In the continuous process of the character above described, it is preferred that the clay or equivalent shall be passed through the system countercurrent to the flow of the oil, so that untreated oil is acted upon first by partially spent clay, while partially treated oil is treated by fresh and/or revivified clay. It will be understood, however, that our invention is not limited in this respect, for the contact of oil with clay may be effected in a single stage, or when effected. in several stages the clay may be passed concurrent with the oil, or the clay utilized in any stage may be there employed until ex hausted, and not passed to any other stage.

Throughout the treatment above described, the oil is maintained at elevated temperature, due either to the heating solely at the heater B or by application of additional heat in or adjacent any one or more of the subsequent agitating chambers or settling tanks. Furthermore, the temperature may be maintained by suitably heat-insulating or j acketing any one or more of the agitating chain hers and settling tanks.

Referring to Figs. 3 and 4:, illustrative of a batch process in accordance with our invention, the oil treated may be of any of the characters hereinbefore referred to. the example illustrated it may be delivered through the pipe 1 into the agitator or acidtreating chamber A, into which acid delivered through the pipe 2 and air .f or agita tion is delivered through the pipe 3, as here- .inbefore described in connection with the continuous process. The sludge is drawn oil. through pipe in this cased the sour oil is pumped directly through the pipe 7 by the pump P and pipe 8 to the coil 9 of tl e heater B, where the oil is raised to a temperature of the order hereinbefore stated. The hot sour oil then passes into the blowin or agitator tank or chamber C, which prefer ably is provided on its exterior with suitable lagging or heat insulation (a Air or equiv lent is introduced under pressure through the supply pipe 10 and tlu-ough the perfoh ated distributors 11., with consequent removal. of moisture, sulphur dioxide, l. fresh dry clay, finely divided as aforesaid. is introduced, as through a chute 2:), and the mixture agitated and blown by the air. The blowing is continued for a suitable length of time to effect the desired purificanon of the oil, comprising decolorisation and neutrali. ion. After suitable period of time. the agitation is discontinued, where upon the 'alre is opened and the mixture of oil and. clay is forced by the pump to Hill a filter, as K, from which the fiinished oil, still hot, is delivered to storage or any other desired destination. The filter cake of clay and contained oil may be treated for recovery and separation by'any suitable method.

The use of a slurry of oil and partially spent clay is applicable also to a batch process of the character described, .in certain cases. For example, the slurry of oil and clay from the treatment of a light colored oil may be used for the treatment of a darlrer oil, it the difference between the physical properties of the two materials is not suiticiently marked as to cause the darker product to be materially affected by the addition of the oil in the sl 1.1. Furthermore, the slurry from the ba ch treatment of certain stocks with the addition of a small quantity of fresh and/or revivified clay, be used for treating another batch of the same stock.

In the process herein described, the clay, as fullers earth, acid-treated California clay, or the like, is in a state of fine sul division, as, for example, such that about 40% will pass through a 200 mesh sieve. The amount of clay used may be from about 1% to about 50% by Weight of the oil treated. The amount of clay required depends upon the type of oil and its previous history or treatment. F or such oils as are normally acid-treated and thereafter neutralized by alkali, clay in the amount of about 3% to about 5% by weight of the oil is ordinarily used, whereasfor oils which are not acid treated clay to the amount of about 40% to about 50% by weight may be used. some circu'n'istances, as above described, clay to the extent of as low as 1% by weight of the oil may be sufficient.

\Vhile air is preferred for agitating and blowing the oil in the presence of clay, it will. be understood that any other suitable gas containing oxygen. may be used. Air, aerifcrous or oxygen-containing gas, such as gaseous products of combustion, flue gas and the like, may be utilized, since in accordance with our process, particularly at the low temperatures employed, substantial oxidation of the oil or oxidation thereof to an extent to affect color, does not occur. In any event, it s charactcristic o Four process that oxygen or a r need. not be excluded from contact with the oil in any stage, particularly during contact with clay or equivalent, and mechanical agitating mechanism may be dispensed with, though it will be understooc the oil and clay mixture may be agitated by suitable mechanism whilein contact with air. In the appended claims to this subject-matter the term ail. includes air and equivalent aeriferous and oxygen containing gases.

The temperatures utilized in our process are lower than those ordinarily used in proo Under esses of this general character, in which it has been common to use temperatures of the order of 300 F. In accordance with our invention, such high temperatures are not necessary, and we find it desirable to hold the oil at a temperature below the boiling ioint of nit-er to prevent foaming of the oil due to the moisture remaining in the oil after water settling. t is, however, not our purpose to limit our invention to any specified temperature or range of temperatures.

Furthermore, the blowing after acid treatment removes moisture, efiecting a clear, bright oil as the final. product. This action of esi gcial importance in view of the fact "(rich in accordance with our process may be removed by the air blowing, whereas in "occsses not utilizing air blowing the water aerated from thc'clay is present in the re oil and causes cloudiness upon coolthe moisture be' removed by proloi'rgcd. heating at relatively high temperature.

s treated in accordance with our inn are not subject to appreciable dismation or darkening in contact with air n. containing gases at the tempera utilized. Notwithstanding the fact the oil during treatment may be exposed to air or oxygen for long periods at the aforesaid temperatures, appreciable darkcning of the oil does not occur; on the contrary the air blowing serves to stabilize the the color resulting from the acid and clay treatment. For this reason the usual precautions to avoid oxidation or contact of air withthe oil. may be dispensesd with, and especially the need for speed in practicing the process is eliminated. The fact that the time required for the oil to be treated in accordance with our process need not be limited or shortened without detrimental effect on the oil, makes possible a continuous process, as above described, distinguished from a batch process.

Once the oil has been heated as hereinbeforc described, it remains at elevated temperature throughout the process, and at the end of the treatnent is still at elevated temperature, and while still hot may be passed to storage, where cooling occurs at atural rate. In accordance with our invention, therefore, itis not a characteristic of our process thatthe hot oil is at any stage rapidly or artifically cooled.

In the case of treatment of sour oils as herein described, the use of clay or the like effects neutralization of the oil in addition to its decolorization. 'Nevertheless, in accordance with our invention, other decolorizing iaterials, such as finely divided bone black or equivalent carbonaceous materials, ma be utilized, particularly upon those oils w ich Ull llll) lll) :neeeyra do not require neutralization. r upon oils requiring neutralizations there may be utilized a mixture oi. clay and carbonaceous ma terials.

For the sake of brevity in the appended claims, however, the t rm clay is utilized in a generic sense to include tullers earth and clays proper, and, in addition, equivalent decolorizing materials of any ot the characters herein referred to, or a mixture of them.

lie .'n the term sour oil is employed as defining an acid-treated oil which has not been neutralized.

its appearing in the appended claims the term unrefined defines a hydrocarbon oil or a traction thereof which has not been sub jected to chemical treatment for refining or deeolorising it.

What We claim is:

1. The method of deeolorizing iuirelined hydrocarbon oil, which comprises acid treating the oil, separating from the oil sul tially all of the sludge formed, passing air into the acid-treated unneutralized oil While at elevated temperzdnre to condition the oil for subsequent lay treatmentthereafter adding finely divided clay to the unneutralized oil. and intimately connningling air With the mixture of oil and clay While at substantially el vated ten'iperature below 212 lb.

2. llhe method 0t decolorizing unrefined hydrocarbon oil, which comprises acidtreating' the oil, separating from the oil substantially all of the sludge formed, passing air through the acid-treated unneutralized oil While at elevated temperature to condition the oil for subsequent clay treatment, thereafter continuously flowing the unneutrelized oil through successive stages, eontinuously passing clay in succession through later and earlier of said stages, intimately commingling air with the oil and clay 1I1lX- ture in least one of said stages, and maintaining toe oil and clay mixture in each of said stages at elevated temperature,

3. The method of? decolorizing unrefined hylrocarbon oil, which comprises acidthe oil, separating from the oil ing -ir through the acid-treated unneutralwhile at an elevated temperature to substantially all of the sludge termed, passcondition the oil for subsequent treatment,

thereafter adding finely divided clay to the zed oil, and intimately 0011111111115 lin air With the mixture While at a tempen ature Within the range from about 150 to 21.0 ees F.

THOli iAS G. DELBRIDGE. HENRY F. DUKE. 

